Caledonian intrusive rock body is newly discovered in the Maerzheng region in the south area of East Kunlun Mountains. Based on zircon U-Pb dating, the age is determined to be Early Ordovician. The lithology is composed of some tonalite, a few of anorthosite and diorite-porphyry. According to research on petrologic and geochemical characteristics of intrusive rocks, the content of Na2O is much richer than that of K2O in basic and acid rocks, which shows characteristics of rich Na. The rock body is characterized by obvious fractionation of REE, enrichment of LREE, weak nagative Eu anomaly.The rock body is characterized by richment of Ba, Th, Zr and depletion of Nb.